Package com.github.tommyettinger.ds.support.sort

Class CharComparators

java.lang.Object

com.github.tommyettinger.ds.support.sort.CharComparators

public final class CharComparators
extends Object

A class providing static methods and objects that do useful things with comparators.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	CharComparators.NaturalImplicitComparator	A type-specific comparator mimicking the natural order.
protected static class	CharComparators.OppositeComparator
protected static class	CharComparators.OppositeImplicitComparator	A type-specific comparator mimicking the opposite of the natural order.

Field Summary

Fields

Modifier and Type	Field	Description
static final CharComparator	NATURAL_COMPARATOR
static final CharComparator	OPPOSITE_COMPARATOR

Method Summary

Modifier and Type	Method	Description
static CharComparator	asCharComparator(Comparator<? super Character> c)	Returns a type-specific comparator that is equivalent to the given comparator.
static CharComparator	oppositeComparator(CharComparator c)	Returns a comparator representing the opposite order of the given comparator.
static void	sort(char[] items, int from, int to, CharComparator c)	Sorts the specified range of elements according to the order induced by the specified comparator using mergesort.
static void	sort(char[] items, CharComparator c)	Sorts all of items by simply calling sort(char[], int, int, CharComparator), setting from and to so the whole array is sorted.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

NATURAL_COMPARATOR

public static final CharComparator NATURAL_COMPARATOR

OPPOSITE_COMPARATOR

public static final CharComparator OPPOSITE_COMPARATOR

Method Details

oppositeComparator

public static CharComparator oppositeComparator(CharComparator c)

Returns a comparator representing the opposite order of the given comparator.

Parameters:

c - a comparator.

Returns:

a comparator representing the opposite order of c.

asCharComparator

public static CharComparator asCharComparator(Comparator<? super Character> c)

Returns a type-specific comparator that is equivalent to the given comparator.

Parameters:

c - a Comparator of Char values.

Returns:

a type-specific comparator representing the order of c.

sort

public static void sort(char[] items,
 CharComparator c)

Sorts all of items by simply calling sort(char[], int, int, CharComparator), setting from and to so the whole array is sorted.

Parameters:

items - the char array to be sorted

c - a CharComparator to alter the sort order; if null, the natural order will be used

sort

public static void sort(char[] items,
 int from,
 int to,
 CharComparator c)

Sorts the specified range of elements according to the order induced by the specified comparator using mergesort.

This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort. The sorting algorithm is an in-place mergesort that is significantly slower than a standard mergesort, as its running time is O(n (log n)²), but it does not allocate additional memory; as a result, it can be used as a generic sorting algorithm.

If and only if c is null, this will delegate to Arrays.sort(char[], int, int), which does not have the same guarantees regarding allocation.

Parameters:

items - the char array to be sorted

from - the index of the first element (inclusive) to be sorted.

to - the index of the last element (exclusive) to be sorted.

c - a CharComparator to alter the sort order; if null, the natural order will be used